Febmix question.

gooty

New Member
I know most people say to read the instructions or just throw in a cap full of febmix but I would like to know what the actual amount should be.

The instructions give 2 ways of calculating it.

1) 125ml-250ml Febmix : 50Kg cement

2) 1L Febmix : 200 litres water

As most people use 14L buckets, I guess it would make sense to weigh a bucket of cement and do the sums accordingly. Although I guess the weight could differ depending on how compressed the powder is.

If measuring by water, I calculate you'd need 70ml of Febmix in 14 litre bucket of water. Thats way more than a cap full. More like 7!!!!

I know I'll now be bombarded by the usual response, but it would be nice to have sensible answers for a change.
 
OK, so I've filled a 13 litre bucket with cement, and it weighs 15.5Kg.

That works out at 38.75ml of Febmix (at the lowest ratio of125ml:50Kg)
 
You got too muc
I know most people say to read the instructions or just throw in a cap full of febmix but I would like to know what the actual amount should be.

The instructions give 2 ways of calculating it.

1) 125ml-250ml Febmix : 50Kg cement

2) 1L Febmix : 200 litres water

As most people use 14L buckets, I guess it would make sense to weigh a bucket of cement and do the sums accordingly. Although I guess the weight could differ depending on how compressed the powder is.

If measuring by water, I calculate you'd need 70ml of Febmix in 14 litre bucket of water. Thats way more than a cap full. More like 7!!!!

I know I'll now be bombarded by the usual response, but it would be nice to have sensible answers for a change.
You got too much time on your hands
 
These companies spent a lot of time/money producing this product. They give mixing instructions for a reason. Too much plasticiser, and the strength of the mix will be compromised. Too many air bubbles are formed which substantially weakens the cement mix. I couldn't find the answer so thought I'd help everyone on the forum for a quick easy rule. Add 39ml of Febmix for every 14L bucket of cement.
I don't know how many ml in a 'cap full' but I'd guess it's around 10ml. I'll check when I get a chance, then feedback. It's not about 'having too much time'. It's about helping each other out rather than constantly replying with childish remarks.
 
That was a good guess. It's exactly 10ml.

So you need 4 capfuls of Febmix to every 14L buckets of cement.
 
On this rare occasion I'd disagree with Malc above.

I used to do it that way, but when you bash it with the water you get inconsistent results, especially when using bulk bags.


As you get through the bag, the lower down you go the more moisture is in the sand - hence you use less gauging water and therefore less admix per guage.


I keep the water clean, small amount to start, then before any sand or cement goes in - admix first - let it turn then begin mixing.
 
As for the ratio, I found this on the sika website.

Bit of maths needed to equate the ratio.

250-500 per 50kg cement or 20 to 40 parts water per 1 part admix


This is for their (ever build) 3 in 1 admix.
Looks like you'd adjust yours pro rata.
 
I don't know about the sand around the rest of the UK, but if you use Febmix at the highest recommended dose with my local Essex sand you might as well not bother.
I've worked on loads of sites over the last 41 years and I've never seen a plasterer or brickie using it at the correct dose.
 
Top